(Update:) Fedora: Chronicle of a Server Break-in

Paul Frields's Update and Report on Fedora August 2008 Intrusion on the fedora-announce-list reads like a detective novel. It all started on August 12, 2008, when a cron job on a Fedora host reported an error. While reviewing the logs, Fedora admins found a change in the package complement that no one could explain. On short notice, the changes turned out to be tampering by an intruder. The project notified the community of the break-in and promptly pulled the server off the net.

It's now become clear how the rogue entered the server structure: he used no hacker tools, but simply authenticated himself using a copy of an SSH private key that was not passphrase-protected. The key belonged to a Fedora admin and in the log entries it showed that the intruder also cracked or knew the admin's password. How the intruder got to the SSH private key, however, nobody knows.

One of the compromised computers also contained the Fedora package signing key. The intruder created modified versions of the two packages OpenSSH and RPM to get to user passwords and, eventually, the password for the package signing key. Had he been successful, he could have introduced fraudulent packages into the repository. Fortunately the investigation found that
Fedora admins discovered the modified packages before anyone could use the server for package signing.

To mitigate any risk of this ever happening again, the Fedora project quickly rebuilt their entire infrastructure, generated new package signing keys and came up with a new security policy. In a week the most essential systems were back to normal and all admins got new SSH keys. A new repo security policy also required Fedora admin groups to use passphrases on their private keys, a definite break from the past.

Frields assured users that no compromised packages were ever delivered as a result of this break-in, either from the master repository or the mirror sites. He went on to thank the Red Hat security response team for their timely assistance.